The second Service Pack for Microsoft Windows Vista has been in the works and is now entering preview beta testing and expected to be released in the first half of 2009. The first Windows Vista Service Pack 1 (SP1) addressed a wide variety of complaints and pain people were reporting with the initial release of Windows Vista. Windows Vista Service Pack 2 (SP2) is doing the same by increasing performance, security, and stability. I like Windows Vista personally and would not go back to Windows XP.
You can now download Vista SP2 Beta through the Customer Preview Program (CPP).
On the Autodesk Platform Team we are testing both the upcoming Windows Vista SP2 and the upcoming Internet Explorer 8 with our products to make sure nothing surprises us or our customers.